3. Using It: HTML
i) To use the upside down exclamation in HTML, you can use any of these three codes: ¡ or ¡ or ¡. All three of these codes are totally synonymous.
ii) The first code, ¡, is called a named character entity, because it "names" the character (inverted exclamation). The next two characters are called numeric character references. They refer to the character with numbers. The two values (#161 and #a1) are actually the same number. You can learn more about this, in the next two sections.
iii) Copying and pasting the upside down exclamation itself (¡) will work if the HTML document is served using a Unicode encoding such as UTF-8. Remember that the document must also be saved in the same encoding that it is being served in (this might involve setting your text editor to, for example, UTF-8).
iv) Our recomendation would be to use one of the HTML codes (i) instead of copying/pasting (iii).